1. Field of Invention
The present invention relates to triterpene derivatives usable as therapeutic agents for hepatic disorders.
2. Description of the Related Art
A liver is an important organ which has various functions necessary for maintaining life of a living body, such as detoxication, various metabolisms, and storage of substances. It, however, often undergoes acute or chronic damage due to viruses, drugs, alcohols and other various causes. This induces viral hepatitis, drug-induced hepatopathy, alcoholic hepatopathy, fatty liver, and, in addition, diseases such as cirrhosis and hepatic cancer.
For treating such disorders, alimentary therapy, rest cure, and other therapies using glycyrrhizin preparations, adrenocortical steroids, interferons and the like have hitherto been employed. These therapies, however, may not be satisfactorily effective for the treatment of the hepatic disorders. Glycyrrhizin and interferon are intravenously administered and, hence, unsuitable for prolonged administration. Further, the interferon and steroids have a problem of side effect.
Some triterpene derivatives have anticomplementary activity and platelet aggregation inhibitory activity. Thus, they are known as prophylactic and therapeutic agents for immunological diseases and thrombosis (Japanese Patent Laid-Open No. 85344/1986). Further, triterpene derivatives are disclosed, for example, in Japanese Patent Laid-Open No. 37749/1986, Chem. Pharm. Bull., 36, 153 (1988), Chem. Pharm. Bull., 24, 121 (1976), Chem. Pharm. Bull., 30, 2294 (1982), Chem. Pharm. Bull., 33, 4267 (1985), Chem. Pharm. Bull., 31, 664 (1983), Chem. Pharm. Bull., 31, 674 (1983), Phytochemistry 27, 3563 (1988), Planta Medica 46, 52 (1982), J. Chem. Soc., and Chem. Comm., 785 (1982).
However, so far as the present inventors know, there is no report which discloses that the triterpene derivatives are effective as a therapeutic agent for treating hepatic disorders.